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      <td><p class="toc level1"><a href="docinfo.html">Document Information</a></p>
<p class="toc level1 tocsp"><a href="gexaf.html">Preface</a></p>
<p class="toc level1 tocsp"><a href="gfirp.html">Part&nbsp;I&nbsp;Introduction</a></p>
<p class="toc level2"><a href="bnaaw.html">1.&nbsp;&nbsp;Overview</a></p>
<p class="toc level2"><a href="gfiud.html">2.&nbsp;&nbsp;Using the Tutorial Examples</a></p>
<p class="toc level1 tocsp"><a href="bnadp.html">Part&nbsp;II&nbsp;The Web Tier</a></p>
<p class="toc level2"><a href="bnadr.html">3.&nbsp;&nbsp;Getting Started with Web Applications</a></p>
<p class="toc level2"><a href="bnafd.html">4.&nbsp;&nbsp;Java Servlet Technology</a></p>
<p class="toc level2"><a href="bnagx.html">5.&nbsp;&nbsp;JavaServer Pages Technology</a></p>
<p class="toc level2"><a href="bnajo.html">6.&nbsp;&nbsp;JavaServer Pages Documents</a></p>
<p class="toc level2"><a href="bnakc.html">7.&nbsp;&nbsp;JavaServer Pages Standard Tag Library</a></p>
<p class="toc level2"><a href="bnalj.html">8.&nbsp;&nbsp;Custom Tags in JSP Pages</a></p>
<p class="toc level2"><a href="bnaon.html">9.&nbsp;&nbsp;Scripting in JSP Pages</a></p>
<p class="toc level2"><a href="bnaph.html">10.&nbsp;&nbsp;JavaServer Faces Technology</a></p>
<p class="toc level2"><a href="bnaqz.html">11.&nbsp;&nbsp;Using JavaServer Faces Technology in JSP Pages</a></p>
<p class="toc level2"><a href="bnatx.html">12.&nbsp;&nbsp;Developing with JavaServer Faces Technology</a></p>
<p class="toc level2"><a href="bnavg.html">13.&nbsp;&nbsp;Creating Custom UI Components</a></p>
<p class="toc level3"><a href="bnavh.html">Determining Whether You Need a Custom Component or Renderer</a></p>
<p class="toc level4"><a href="bnavh.html#bnavi">When to Use a Custom Component</a></p>
<p class="toc level4"><a href="bnavh.html#bnavj">When to Use a Custom Renderer</a></p>
<p class="toc level4"><a href="bnavh.html#bnavk">Component, Renderer, and Tag Combinations</a></p>
<p class="toc level3 tocsp"><a href="bnavm.html">Understanding the Image Map Example</a></p>
<p class="toc level4"><a href="bnavm.html#bnavn">Why Use JavaServer Faces Technology to Implement an Image Map?</a></p>
<p class="toc level4"><a href="bnavm.html#bnavo">Understanding the Rendered HTML</a></p>
<p class="toc level4"><a href="bnavm.html#bnavp">Understanding the JSP Page</a></p>
<p class="toc level4"><a href="bnavm.html#bnavq">Configuring Model Data</a></p>
<p class="toc level4"><a href="bnavm.html#bnavr">Summary of the Application Classes</a></p>
<p class="toc level3 tocsp"><a href="bnavt.html">Steps for Creating a Custom Component</a></p>
<p class="toc level3"><a href="bnavu.html">Creating Custom Component Classes</a></p>
<p class="toc level4"><a href="bnavu.html#bnavv">Specifying the Component Family</a></p>
<p class="toc level4"><a href="bnavu.html#bnavw">Performing Encoding</a></p>
<p class="toc level4"><a href="bnavu.html#bnavx">Performing Decoding</a></p>
<p class="toc level4"><a href="bnavu.html#bnavy">Enabling Component Properties to Accept Expressions</a></p>
<p class="toc level4"><a href="bnavu.html#bnavz">Saving and Restoring State</a></p>
<p class="toc level3 tocsp"><a href="bnawa.html">Delegating Rendering to a Renderer</a></p>
<p class="toc level4"><a href="bnawa.html#bnawb">Creating the Renderer Class</a></p>
<p class="toc level4"><a href="bnawa.html#bnawc">Identifying the Renderer Type</a></p>
<p class="toc level3 tocsp"><a href="bnawd.html">Handling Events for Custom Components</a></p>
<p class="toc level3"><a href="bnawe.html">Creating the Component Tag Handler</a></p>
<p class="toc level4"><a href="bnawe.html#bnawf">Retrieving the Component Type</a></p>
<p class="toc level4"><a href="bnawe.html#bnawg">Setting Component Property Values</a></p>
<p class="toc level5"><a href="bnawe.html#bnawh">Getting the Attribute Values</a></p>
<p class="toc level5"><a href="bnawe.html#bnawi">Setting the Component Property Values</a></p>
<p class="toc level4 tocsp"><a href="bnawe.html#bnawl">Providing the Renderer Type</a></p>
<p class="toc level4"><a href="bnawe.html#bnawm">Releasing Resources</a></p>
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<p class="toc level3 tocsp"><a href="">Defining the Custom Component Tag in a Tag Library Descriptor</a></p>
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<p class="toc level2 tocsp"><a href="bnawo.html">14.&nbsp;&nbsp;Configuring JavaServer Faces Applications</a></p>
<p class="toc level2"><a href="bnaxu.html">15.&nbsp;&nbsp;Internationalizing and Localizing Web Applications</a></p>
<p class="toc level1 tocsp"><a href="bnayk.html">Part&nbsp;III&nbsp;Web Services</a></p>
<p class="toc level2"><a href="bnayl.html">16.&nbsp;&nbsp;Building Web Services with JAX-WS</a></p>
<p class="toc level2"><a href="bnazf.html">17.&nbsp;&nbsp;Binding between XML Schema and Java Classes</a></p>
<p class="toc level2"><a href="bnbdv.html">18.&nbsp;&nbsp;Streaming API for XML</a></p>
<p class="toc level2"><a href="bnbhf.html">19.&nbsp;&nbsp;SOAP with Attachments API for Java</a></p>
<p class="toc level1 tocsp"><a href="bnblr.html">Part&nbsp;IV&nbsp;Enterprise Beans</a></p>
<p class="toc level2"><a href="bnbls.html">20.&nbsp;&nbsp;Enterprise Beans</a></p>
<p class="toc level2"><a href="bnbnb.html">21.&nbsp;&nbsp;Getting Started with Enterprise Beans</a></p>
<p class="toc level2"><a href="bnboc.html">22.&nbsp;&nbsp;Session Bean Examples</a></p>
<p class="toc level2"><a href="bnbpk.html">23.&nbsp;&nbsp;A Message-Driven Bean Example</a></p>
<p class="toc level1 tocsp"><a href="bnbpy.html">Part&nbsp;V&nbsp;Persistence</a></p>
<p class="toc level2"><a href="bnbpz.html">24.&nbsp;&nbsp;Introduction to the Java Persistence API</a></p>
<p class="toc level2"><a href="bnbrl.html">25.&nbsp;&nbsp;Persistence in the Web Tier</a></p>
<p class="toc level2"><a href="bnbrs.html">26.&nbsp;&nbsp;Persistence in the EJB Tier</a></p>
<p class="toc level2"><a href="bnbtg.html">27.&nbsp;&nbsp;The Java Persistence Query Language</a></p>
<p class="toc level1 tocsp"><a href="bnbwi.html">Part&nbsp;VI&nbsp;Services</a></p>
<p class="toc level2"><a href="bnbwj.html">28.&nbsp;&nbsp;Introduction to Security in the Java EE Platform</a></p>
<p class="toc level2"><a href="bnbyk.html">29.&nbsp;&nbsp;Securing Java EE Applications</a></p>
<p class="toc level2"><a href="bncas.html">30.&nbsp;&nbsp;Securing Web Applications</a></p>
<p class="toc level2"><a href="bncdq.html">31.&nbsp;&nbsp;The Java Message Service API</a></p>
<p class="toc level2"><a href="bncgv.html">32.&nbsp;&nbsp;Java EE Examples Using the JMS API</a></p>
<p class="toc level2"><a href="bncih.html">33.&nbsp;&nbsp;Transactions</a></p>
<p class="toc level2"><a href="bncjh.html">34.&nbsp;&nbsp;Resource Connections</a></p>
<p class="toc level2"><a href="bncjx.html">35.&nbsp;&nbsp;Connector Architecture</a></p>
<p class="toc level1 tocsp"><a href="bnckn.html">Part&nbsp;VII&nbsp;Case Studies</a></p>
<p class="toc level2"><a href="bncko.html">36.&nbsp;&nbsp;The Coffee Break Application</a></p>
<p class="toc level2"><a href="bnclz.html">37.&nbsp;&nbsp;The Duke's Bank Application</a></p>
<p class="toc level1 tocsp"><a href="gexbq.html">Part&nbsp;VIII&nbsp;Appendixes</a></p>
<p class="toc level2"><a href="bncno.html">A.&nbsp;&nbsp;Java Encoding Schemes</a></p>
<p class="toc level2"><a href="bncnq.html">B.&nbsp;&nbsp;Preparation for Java EE Certification Exams</a></p>
<p class="toc level2"><a href="bncnt.html">C.&nbsp;&nbsp;About the Authors</a></p>
<p class="toc level1 tocsp"><a href="idx-1.html">Index</a></p>
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<a name="bnawn"></a><h3>Defining the Custom Component Tag in a Tag Library Descriptor</h3>
<p><a name="indexterm-1559"></a><a name="indexterm-1560"></a>To define a tag, you declare it in a TLD. The web
container uses the TLD to validate the tag. The set of tags that
are part of the HTML render kit are defined in the <tt>html_basic</tt> TLD.</p><p>The custom tags <tt>area</tt> and <tt>map</tt> are defined in <tt>bookstore.tld</tt>. The <tt>bookstore.tld</tt> file defines
tags for all the custom components and the custom validator tag described in
<a href="bnauw.html#bnauy">Creating a Custom Tag</a>.</p><p>All tag definitions must be nested inside the <tt>taglib</tt> element in the TLD.
Each tag is defined by a <tt>tag</tt> element. Here is part of the
tag definition of the <tt>map</tt> tag:</p><pre>&lt;tag>
    &lt;name>map&lt;/name>
    &lt;tag-class>taglib.MapTag&lt;/tag-class>
    &lt;attribute>
        &lt;name>binding&lt;/name>
        &lt;required>false&lt;/required>
        &lt;deferred-value>
            &lt;type>
                javax.faces.component.UIComponent
            &lt;/type>
        &lt;/deferred-value>
    &lt;/attribute>
    &lt;attribute>
        &lt;name>current&lt;/name>
        &lt;required>false&lt;/required>
        &lt;deferred-value>
            &lt;type>
                java.lang.String
            &lt;/type>
        &lt;/deferred-value>
    &lt;/attribute>
    ...
    &lt;attribute>
        &lt;name>actionListener&lt;/name>
        &lt;required>false&lt;/required>
        &lt;deferred-method>
            &lt;method-signature>
                void actionListener(javax.faces.event.ActionEvent)
            &lt;/method-signature>
        &lt;/deferred-method>
        &lt;type>String&lt;/type>
    &lt;/attribute>
    ...
&lt;/tag></pre><p>At a minimum, each tag must have a <tt>name</tt> (the name of the
tag) and a <tt>tag-class</tt> attribute, which specifies the fully-qualified class name of the
tag handler.</p><p>Each attribute element defines one of the tag attributes. As described in <a href="bnahq.html#bnaia">Defining a Tag Attribute Type</a>,
the attribute element must define what kind of value the attribute accepts, which
for JavaServer Faces tags is either a deferred value expression or a method
expression.</p><p>To specify that an attribute accepts a deferred value expression, you define the
type that the corresponding component property accepts using a <tt>type</tt> element nested
inside of a <tt>deferred-value</tt> element, as shown for the <tt>binding</tt> and <tt>current</tt> attribute definitions
in the preceding code snippet.</p><p>To specify that an attribute accepts a method expression, you define the signature
of the method that expression references using a <tt>method-signature</tt> element nested inside
a <tt>deferred-method</tt> element, as shown by the <tt>actionListener</tt> attribute definition in the preceding code
snippet. The actual name of the method is ignored by the runtime.</p><p>For more information on defining tags in a TLD, consult the <a href="bnamu.html">Tag Library Descriptors</a> section
of this tutorial.</p>
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